Canadian Customs can ask for insurance covering your vehicle while in Canada. We just called our State Farm agent and they emailed us a statement saying it was covered.
You don't need a tourist visa, but pay attention to their Covid vaccine/testing requirements.
No one is going to question you about importing your vehicle for sale in Canada.
If you have a gun and insist on taking it, follow their rules. Not following them will probably get you in more trouble than anything else. I have a friend who insisted on taking his pistol. He got arrested and and lost his TC.
Bill